Remove some migrated builders from the experiment

Also disable all but one mac experiment. Having too many experiments causes
large pending queues to be generated and the builds fail to apply the patch
since they run after the CL has landed.

TBR=machenbach@chromium.org

No-Try: true
Bug: chromium:747960
Change-Id: I1cd21798a17c857d4275d0f15a2b98e13fe9c367
Reviewed-on: https://chromium-review.googlesource.com/839141
Commit-Queue: Sergiy Byelozyorov <sergiyb@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Sergiy Byelozyorov <sergiyb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50256}

infra/config/cq.cfg

@@ -124,30 +124,6 @@ verifiers {
       # migrating them to LUCI. Should be removed after migrating to LUCI. To
       # avoid using too much capacity, only a few of the builders should be on
       # CQ at any given time, thus some of the builders below are commented.
-      builders {
-        name: "v8_mac_gc_stress_dbg"
-        experiment_percentage: 100
-      }
-      builders {
-        name: "v8_mac64_dbg"
-        experiment_percentage: 100
-      }
-      builders {
-        name: "v8_linux64_ubsan_rel_ng"
-        experiment_percentage: 10
-      }
-      builders {
-        name: "v8_win_asan_rel_ng"
-        experiment_percentage: 100
-      }
-      builders {
-        name: "v8_linux_arm_dbg"
-        experiment_percentage: 10
-      }
-      builders {
-        name: "v8_mac64_asan_rel"
-        experiment_percentage: 100
-      }
       builders {
         name: "v8_linux64_msan_rel"
         experiment_percentage: 10
@@ -164,10 +140,6 @@ verifiers {
         name: "v8_linux_nosnap_dbg"
         experiment_percentage: 10
       }
-      builders {
-        name: "v8_mac64_rel"
-        experiment_percentage: 100
-      }
     }
     buckets {
       name: "master.tryserver.chromium.win"